This invention relates generally to the navigation of a moving vehicle. In particular, this invention relates to a method and system for detecting geometric anomalies on a road that provide useful navigational information to a moving vehicle.
Digital map databases typically provide enough information to determine accurately road geometry. Often, this information does not provide any advance warning or information about a severe change in upcoming road geometry. Severe road changes may be a result of inclement weather or construction. Information about the upcoming geography may be especially beneficial if the condition is a steep upgrade or downgrade. Ideally, this type of information may be used to control or influence vehicle speed when given road conditions require slower speed.
It would be desirable, therefore, to provide a method for detecting geometric anomalies on a road, providing useful information to a moving vehicle that overcomes the above-mentioned navigational difficulties.
One aspect of the present invention provides a method for providing road condition information to a mobile vehicle. A plurality of road points is received on the vehicle client from the navigation subsystem server. A road profile value based on at least a portion of the road points is determined and it is determined whether the road profile value exceeds the road profile threshold value. A suggested vehicle speed may be computed when the road profile value exceeds the road profile threshold value. The suggested vehicle speed is compared to a sensed vehicle speed, and an excessive speed alert is sent to the vehicle based on the comparison.
Another aspect of the present invention provides a system for providing road condition information to a mobile vehicle. The system may include means for receiving a plurality of road points for determining a road profile value based on at least a portion of the road points, and for determining whether the road profile value exceeds a road profile threshold value. It may also include means for computing a suggested vehicle speed when the road profile value exceeds the road profile threshold value, by comparing the suggested vehicle speed to a sensed vehicle speed, and then sending an excessive speed alert to the vehicle based on the comparison.
Another aspect of the present invention provides a computer usable medium including a program for providing road condition information to a mobile vehicle. The program may include computer readable program code that determines a road profile value based on at least a portion of received road points, computer readable program code that determines whether the road profile value exceeds a road profile threshold value and computer readable program code that computes a suggested vehicle speed when the road profile value exceeds the road profile threshold value. It may also include computer readable program code that compares the suggested vehicle speed to a sensed vehicle speed and computer readable program code that sends an excessive speed vehicle alert based on the comparison.
The foregoing and other features and advantages of the invention will become further apparent from the following detailed description of the presently preferred embodiments, read in conjunction with the accompanying drawings. The detailed description and drawings are merely illustrative of the invention rather than limiting, the scope of the invention being defined by the appended claims and equivalents thereof.